Electronic devices, such as portable computers, are equipped with a tracking device or a cursor-controlling device for user input of instructions and data. A variety of tracking devices are known, such as a computer mouse that is connected to a computer by a mouse cable, a tracking ball that is mounted in the casing of a portable computer, a digitizer that is connected to a computer by a cable and requires a stylus for input of data and instruction and a touch pad that is usually mounted on the casing of a computer and allows a user finger to touch and move thereon for controlling the cursor on a computer display. Often, a couple of pushbuttons are mounted next to the touch pad to help the operation thereof.
Conventionally, the touch pad pushbuttons are separate parts of the computer casing and are movably supported by biasing elements, such as springs, above a circuit of the touch pad whereby striking a pushbutton causes a physical engagement of the pushbutton with the circuit thereby initiating generation of a signal through the circuit for indication of the striking of the pushbutton. Such pushbuttons may accidentally get out of position during the operation thereof. In addition, the conventional pushbuttons require a sophisticated assembly process, which adds to the overall manufacturing cost of the electronic devices.
Thus, it is desired to have a touch pad pushbutton structure that overcomes or at least alleviates the problems discussed above.